1. A power consumption measuring device comprising an analog-to-digital converter and an arithmetic unit and adapted to convert an electrical signal supplied to a load into a measurement digital signal by means of the analog-to-digital converter and send the measurement digital signal to the arithmetic unit for measuring a power consumption level of the load, the power consumption measuring device being characterized in that the arithmetic unit comprises:
a gain adjustment unit configured with at least two current gain values each corresponding to a current range;
a correction unit having at least two correction compensation values defined by the at least two current gain values, respectively, and defined in order to eliminate an internal impedance of the power consumption measuring device while being corresponding to the current gain values, respectively; and
a control unit connected to the gain adjustment unit and the correction unit for configuring the current ranges corresponding to the current gain values, respectively, and selecting the current gain values and the correction compensation values based on the current range into which the measurement digital signal falls, so as to adjust the gain value of the analog-to-digital converter.
2. The power consumption measuring device of claim 1, wherein the gain adjustment unit provides a first current gain value and a second current gain value and provides a first correction compensation value and a second correction compensation value which correspond to the first current gain value and the second current gain value, respectively, wherein the second current gain value and the second correction compensation value are greater than the first current gain value and the first correction compensation value, respectively, wherein the control unit sets two adjacent ones of the current ranges to one above a current threshold value and another one below the current threshold value, wherein the control unit selects the first current gain value and the first correction compensation value whenever the measurement digital signal falls into the current range below the current threshold value.
3. The power consumption measuring device of claim 2, wherein the control unit sets the current threshold value to 500 mA.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A system for performing a ground vibration test on an airplane, comprising:
a plurality of vibration exciters coupled to a plurality of locations on the airplane that operate to excite the airplane to vibrate;
a plurality of measuring transducers coupled to the airplane and operating to produce a plurality of measuring values;
at least one holding device, including a hydraulic lift, that provides an undamped, and substantially rigid support for the airplane between the airplane and ground; and
a processing system comprising an evaluator that implements a predetermined, simple, rigid holding model for the substantially rigid support.
2. The system of claim 1, wherein the at least one holding device includes at least three hydraulic lifts, at least one of the hydraulic lifts operating to couple a respective one of at least three holding points on the airplane to provide the undamped, and substantially rigid support between the airplane and ground.
3. The system of claim 1, wherein the plurality of vibration exciters include electromagnetic exciters.
4. The system of claim 1, wherein the vibration exciters are positioned in at least one of wing ends, elevator unit ends, a rudder unit end, an aft fuselage, engines, and a nose of the airplane.
5. The system of claim 1, wherein the measuring transducers are arranged at at least one of on and inside the airplane.
6. The system of claim 1, wherein the plurality of measuring transducers are up to 1,000 in number.
7. The system of claim 1, wherein the measuring transducers include accelerometers.
8. The system of claim 1, wherein the processing system operates to control the vibration exciters, and receive and evaluate the plurality of measuring values from the measuring transducers.
9. The system of claim 8, wherein the processing system includes a vibration model of the airplane.
10. The system of claim 9, wherein the vibration model mathematically treats the substantially rigid support between the airplane and the ground as rigid when evaluating the plurality of measuring values from the measuring transducers.
11. The system of claim 10, wherein the processing system operates to mathematically cancel out the influence that the rigid support of the airplane has on the vibration of the airplane during the ground vibration test.
12. The system of claim 9, wherein the vibration model of the airplane encompasses up to 5\xb7106 node points, each with 6 degrees of freedom.
13. The system of claim 12, wherein the processing system operates to adjust the vibration model of the airplane such that the vibration model is continuously harmonized with the measuring values from the measuring transducers duration the ground vibration test.
14. The system of claim 13, wherein the processing system operates to compare vibration characteristics from the measuring values duration the ground vibration test in a specific set of actuation commands to vibration characteristics corresponding to a same set of actuation commands used in formulating the vibration model.
15. The system of claim 14, wherein the processing system operates to change preset parameters of the vibration model if a difference is encountered or a maximum permissible setpoint-actual value deviation is exceeded during the comparison.
16. The system of claim 15, wherein the processing system operates to change the preset parameters of the vibration model such that the setpoint-actual value comparison falls below the maximum setpoint-actual value deviation value.
17. The system of claim 15, wherein the processing system operates to change the preset parameters of the vibration model via an iterative process.